Ocean Water's Aquarium
by Whistle Mist
Summary: Kotetsu has been raised his whole life in captivity. Being a mermaid and all was a sure way he'd never be set free. It was alright he had Ben, the other people who took care of him. Then one day he got some new company. However, these new Mers all kind of strange to him. Especially that mean one called… uh…. What was his name? Barny?Banny? … Bunny! Yes, that Bunny made him feel r
1. Chapter 1

**I don't own Tiger & Bunny**

* * *

Kotetsu sighed happily as he was pet.

The young Merchild was happily getting pet by two people not noticing that they were using this as an easy way to give him a checkup. He only yelped when they took a blood sample. Whining a bit he turned to see what poked him but was quickly distracted by them handing him a tasty fish.

The caretaker pe behind his long elfish like ears before carefully picking him up and setting him back in the huge pool they had for him. Swimming around Kotetsu whined trying to get back up onto the little deck to be pet some more.

The doctors walked away but the caretaker stayed. This man's name was Ben. He had been put in charge of looking after Kotetsu. The little mermaid wasn't sure but he had been given a new name by these people. They called him Tiger for some reason.

It would take a few weeks but eventually, Tiger knew his name when they called it.

* * *

Years later Kotetsu was squealing with delight when reporters came to visit him. They did almost every year when the big holidays were happening. He was laying on the deck trying to show them his new toy he got. It was a waterproof blue and white tiger that had a hat on it. It was made out of some material so it acted like a chew toy. Popping his head out of the water the young preteen mer swimming up to them squealing and cooing for them to look at his little friend.

They laughed excitedly taking more pictures until Kotetsu was tired of the flashing lights. Swimming away he heard towards a rock they had given him. Pulling himself up onto it he laid down cuddling the toy into his arms before taking a nap.

* * *

It was fairly lonely in the large pool all by himself. Kotetsu only had his small friend with him, the little blue tiger that was now smaller now that he was full grown. A bad habit Kotetsu had with his toy was holding it in his mouth when seeing the humans.

It wasn't like he was nervous… well, just a little bit. It was because of the new humans who visited every day. They were loud, so loud that sometimes it made him slightly nervous so carrying around his tiger in his mouth by it's front arm comforted him.

They seemed to think it was really funny because they always made 'Aww' sounds at him. Going around near the glass he did a few trick to make the strange child who had no tails laugh and cheer.

Swimming around he was happily trying to make friends when there was a sound of splaying around come from above. Looking up Kotetsu strained his ears hearing the sounds. It wasn't Ben. He always patted the water.

Swimming up to see what the noise was he surprised to see someone in his pool. Curious he swam over to the kid who was screaming. The girl saw him and let out a scream. People were yelling in fear. Looking around it hit Kotetsu that maybe humans didn't know how to swim without that odd flat fur they grew. MOving forward ignoring the cries getting louder he bit down on the back of her shirt.

Everyone fell silent as they watched Kotetsu swim towards two people, the girl's parents, sensing that they were the most upset and also smelled like the girl. Sitting up he easily gave her back to them before swimming back down to play with the kids behind the glass.

Cheers could be heard but the merman didn't know why they were so excited. Humans were odd.

* * *

"You did good today Tiger," Ben praised as he pet the mer's head chuckling as the other squealed happily getting the attention. Petting under the chin Ben sighed. "You saved that little girl today. I bet you don't really understand it but you're all over the news today."

Almost like purring Kotetsu tried to lay down so his side could be pet. Normally Ben stuck around for a few minutes extra if he didn't this. Sighing happily as his side was being et he was ready to take a nap when there was a loud clang.

Startled Kotetsu jumped down into the water swimming fast into his little cave.

Standing Ben hurried over to where they had been bringing a transfer tank. It looked like it had slipped from the ropes before banging right into the main water pipe that kept their merman's pool filled.

"Mr. Jackson, there's a huge leak."

"Quick get the medical tank ready just in case we need to keep Tiger wet!"

* * *

Kotetsu had no idea what was happening or why he was in the sick tank but he didn't know they didn't have enough of the right water. Panting he poked his head out of the tank whining miserably.

When Ben rushed over to check what was going on he hadn't realized he was still whimpering from having such a hard time getting enough water into his gils. He could breathe air, yes, but most of the time it was water.

"It's going to be alright, Tiger, just hang in there, we're getting ou a temporary tank soon."

Whatever the human as saying fell on deaf ears because Kotetsu felt like passing out. Letting out a distressed cry he wiggled sluggishly. A hand ran through his hair but the normal attention that he loved was all but gone now.

"Just a few more hours, okay? I promise." Worried Ben picked up the phone. "Sir, Tiger's not doing so well… yes, yes, I understand. Of course, see you when you get here."

Almost five hours later the tank arrived barely big enough for Kotetsu but it was perfect because after a few minutes the mer perked up before making odd motioning, noises, and coos. Ben smiled before he held up a toy tiger slipping it into the tank.

"There you go, boy, I had to wait for the pool to drain all the way before finding him."

* * *

Ten years later Kotetsu had grown lonely being in a huge tank by himself.

The small aquatic center had been bought five years ago before being torn down and rebuilt. In that time Kotetsu had spent a good amount of being stuck in a small pool in a blank room with only a ten by fifteen feet to move in. The tank only went up five feet and had bar top over it to keep him from jumping out.

Spending two years like that along with little company save for the janitors who came into clean, often talking and playing with him for a little bit, (They would smile when the merman greeted them so excitedly, sometimes sneaking him little sardines,) Ben who visited almost everyday trying to pet him for a while, getting him to move more, another caretaker who would check in for a few minutes and once in awhile the owner came to see him.

However most of the day he was lonely so he spent his time chewing nervously on his tiger's arm before calling for anyone's to come see him. Maybe he cried out painfully or too much because suddenly everyone started to sneak him food.

Still, alone Kotetsu decided to eat. Just eat anything and everything they gave him. Even if his stomach hurt the pain of being alone made him want to fill that void so he ate, ate until Ben noticed his small mer was suddenly gaining weight like crazy.

Concerned it was a medical reason they moved him out to another center so they could use the equipment. When they checked him realizing somehow he had been overfed. Once they figured it out they placed a sign over the tank saying not to feed the mer before Ben went to see if there was a bigger place to keep Tiger until the huge pool was ready.

Sadly Tiger ended up back in the roll for almost another year.

* * *

Tiger almost threw himself out of the small tank into the gigantic pool the second they opened the lid. He was almost there but then something made him gag as a thick thing suddenly came around his neck.

Hissing Tiger dove back into the little tank his hands reaching up to tug at the tight thing around his neck. Whimpering he trashed around in the water trying to free himself when a familiar part of water made him stop looking up.

Sliding halfway out of the tank Kotetsu presented his neck to Ben showing him the tight thing that was put on him. The large hands reached over carefully loosening the thing until it fit snuggly instead of tight.

"Alright, Tiger, see? All fix," Ben eased the Mer out of the tank before setting him in the water so he could swim off. "Go enjoy your new home."

Letting out an excited squeal they watched as Tiger explored the pool. However, he came back a few minutes later just staring at them with his mouth open. Ben paused before looking at the little tank to see the tiger. Laughing he fished it out before placing he hand in Tiger's mouth watching him swim off to go hide his little friend.

* * *

Trimming mermaid nails took a good hour to do. Filing down the sharp nails into dull short ones was something they did to make sure the mermaids didn't harm themselves or others but trimming them proved harder with Tiger because he wanted attention.

The woman laughed as she almost got done with a third nail and the mer pushed his head up against her chin trying to get a pet.

"Alright, alright, I'll pet you for a few minutes then we get your nails taken care of."

It ended up taking an hour and a half before Tiger's claws were once again filed down to short smooth nails. Tiger cried sadly as she left. It was something everyone noticed was how after Tiger had been placed back into a large home he had gotten upset about being left alone.

It even reached the owner's noticed when fans of the mer had wrote in to complain that their happy friendly mer was now looking sad and lonely. Luckily for it, the Owner had just gotten some news about another Aqua center that was being shut down due to the abuse of their animals and he had just purchased a few new friends for his little money maker.

* * *

"No, Tiger, no," Ben scolded gently before he held up the toothbrush again. "Say 'Ah.' come on now, the sooner the better."

Huffing Tiger opened his mouth so Ben could use that thing to clean his fangs. It always felt odd no matter how old he got. He didn't like it but there was promising sweet snack waiting for him if he did.

"There, all done." Ben laughed petting the other's hair and under his chin. "See? ONly three minutes."

Shaking his head Tiger pointed to the bucket just out of reach.

"Ah, you can smell it huh?" standing Ben walked over to the bucket putting a live fish out herding the excited splashing behind him. Walking over he leaned down as he saw Tiger opening his mouth wide, eyes closed. "I wonder if you still think you're a child? Here you go,"

Quickly biting the bite so it died Kotetsu smiled happily.

"Well, I have some good news for you, buddy," Ben said as he pet the mer some more. "You're going to be getting new friends soon."

* * *

 **Contiune or not? I'm not sure, but I kinda like this AU, kinda not so much.**

 **Let me know! ;D**


	2. Chapter 2

Kotetsu was laying in the water inside the large aquarium where they had a good foot and a half of water by where the human children could play with the fish. Only three years ago they had let him swim into the little place for the children to pet him.

Sometimes he even took a nap while all the hands were petting him. After a while, he learned smaller ones likes to yank hair. So, when they did He easily took their hands off slowly before moving away from a little.

Some of the humans who were grown like Ben like to ruffle his head. Sometimes a bit too hard because they mistake him to be what they called a 'dog'. WHoever 'dog' was they must like their heads pet hastily.

The old ones must have been his favorites. They would sit on a chair next to the small pool running their hands over his head, back and sometimes under his chin. They also talked to him a lot. Not much he understood but he would respond depending on the tone of their voices. Maybe he did something right because they all left happy.

At the moment Kotetsu was laying sideways with his head on an old woman's lap as she pet his head speaking softly about something or others when there was a chatter of excitement. OPening one sleep eye he thought of going to see what it was but then again…. Just a little while more… besides his friend smelled like she wasn't going to be around much longer and he was going to miss her since she often came to see him.

* * *

Getting hungry Kotetsu heading down to his little cave to gather some snacks he had hidden in a little net. Ben had given him the tiny net to keep a few tasty fish in. Taking two out he quickly killed them before eating them.

Swimming back up to the surface to see what was going on with he noticed they were struggling with a tank. Frowning he wondered if he was going in there. After all, he was just in the Med tank just a few moons ago getting a checkup.

Peeking out he saw something inside it. Curious about what could be inside he swam over to the edge to try to take a closer look. A light purple and white tail caught his attention. Wait… was that… someone like him?!

Chipping excitedly he got the attention of the humans who noticed him. One of them tried to shoo him away, another laughed before they kept moving.

Following them as much as he could Kotetsu was started to get disappointed when little kid music started playing. Kids. The kids were here! Happily swimming off to go see them he was surprised that the door to the petting tank was closed.

Whining he could see all the kids on the other side looking for him. Whining louder he tapped on the glass trying to get it to open. Instead, there was a small sound of beeps that meant Ben wanted to see him.

COnfused Kotetsu decided to go see what was going on. Hopefully, it as the little room again because that was horrible. Swimming over to the tube that leads to his inside tank be popped up calling out happily.

"There you are, Tiger," Ben greeted before kneeling down to pet him. "How've you've been today?"

Purring happily as he was pet under the chin he noticed that tank again. Letting out a curious noise Ben stood up chuckling.

"One of your friends came in today…. But he's still pretty young... So, I"m going to need you be nice."

They wheeled the tank over to the shallow pool with the whirling on a glass being shut out keep either mer from leaning. A good six feet deep and a twenty feet long they were carefully dumping the new Mer in but the fear was clear as the new one jumped from the tank to the water trying to flee.

The little mer ended up curling into a ball at the bottom in the far left side of the pool. Curious to see what in the world this new friend was Kotetsu swam over slowly looking at the trembling mer who jumped looking at him before looking away.

Meanwhile Ben was watching them closely. They had a few sedatives on hand that would be easy if they needed it but other then that they hoped that even though Tiger had rarely seen another Mer, save for ones they showed him on waterproof tablets.

Tiger made a few handwaves before swimming over to the door trying to get out. DIsappointed Ben told them to open the door. He didn't need a fight. However only a minute or two later Tige returned with his little toy going over to the scare Mer nudging him with the toy.

Slowly the other Mer looked over before taking the little tiger slowly before looking sadly at Tiger as if he was crying before Tiger swim slowly away from the little mer following him. Seeing that it seemed fine Ben had them open the little glass door letting both of them out.

* * *

"Origami and Tiger as getting along well," Ben noted as he watched the cameras as the new Mer, Named Origami, followed Tiger around almost as if afraid he'd vanish if they were separated. "According to the file Origami was the youngest at the old place… abused so he probably feels safer with someone older around him."

"Dr. Jackson, we have news that the others are on their way over soon," Spoke Dr. Saito as he turned window on the tablet. "Another young one… they call her Dragon."

"I heard there was a female one… but they can't figure out if she's a child or a teen…. Remember how long it took for Tiger to get older?"

"Sometimes I think he never grew up," Dr. Saito laughed before looking at the camera where Tiger was in the petting pool getting pet by some kids, Origami just peeking out of the water through the little tunnel looking scared about going over, but not wanting to let the other out of his sight and he noticed that the new mer had something familiar in his mouth. "Hey, he still hasn't let go of Tiger's little Tiger"

"I think we might have to get one for him to play with," Ben zoomed in a bit. "It looks like it's helping him like it helped Tiger. Alright, I got the report or the boss so I'll leave you to it."

"See you later,"

* * *

Kotetsu was asleep in the cave he now shared with the new Mer, who's named was Ivan, and the young Mer had said that his humans were horrible to him. It sadden Kotetsu that Ivan was so scared of humans that even the little ones frightened him.

"They're not so bad," Kotetsu comforted in their now shared cave as he held Ivan in a tight hug. "Ben is the best human you can know. I've known him my whole life. He gave me this,"

Ivan looked at the little thing he had been carrying around. It brought him comfort for some unknown reason. Still in fear the human's cameras that turned towards them he tried to get closer to Kotetsu whimpering.

"Hey, I know, come with me to see Ben. You'll see how nice he is." Kotetsu let go before swimming out of the cave. "Come on, I'll show you,"

"I don't know,"

"I promise, it's all going to be okay."

Unsure Ivan followed the older Mer old hoping he was right. After all, he did take him into his home. They swam back to the indoor room that he had arrived in. Kotetsu popped his head out of the water calling for the human.

It took a few minutes before Ben came walking out. "Tiger, what's wrong, boy?"

Happily seeing the human Kotetsu waited until he was kneeling on the deck so he could be pet for a minute before looking back to Ivan who looked like he was extremely nervous. Motion for him to swim over.

Slowly Ivan made his way over sticking close to Kotetsu before wincing as the man's hand came to rest on his head. Eyes tight Ivan was ready for a hit or hair yanking but was surprised to feel fingers running through his hair, behind his ears, and under his chin.

"Well, you were just nervous about your new home, huh?" Ben chuckled before petting the new Mer a little more. "I bet you want a treat? Here, you go,"

Ivan looked the little piece of food, not sure what it was but it was really tasty. Taking it under the water to eat it. Popping back up he was giving a little toy like Kotetsu. This one looked a bit strange. Taking it he saw on the things arm, the pressure feeling good on his teeth.

Happily playing with it he hadn't noticed when Ben left. Going under the water he decided to play around with the toy when he finally noticed that Kotetsu was missing. Looking around suddenly feeling alone Ivan was about to panic when he remembers that the doors that opened for the humans to be in the shallow water had opened.

Swimming off he headed to the opening to watch the older Mer being pet by the little humans. They all looked so excited to see him. Still not ready Ivan hung back waiting.

* * *

"Who's a good, boy? WHo's my favorite? You are! Yes, you are!"

Kotetsu currently was having his face squeezed together by an energetic woman who often came to see him around this time. She always did this so he didn't mind...plus she always brought this really good tasty fish.

"Oh, yes, you are, you are, you are!" The woman squealed before finally letting him go. "I got you something! Yes, i did!"

"Mrs. William," Ben greeted as he walked over petting the mer's head. "It's been three months already?"

"It has, Mr. Jason," She grabbed Tiger's face again. "I could wait to see this cutie pie again."

Mewling happily as she waved for them to hand over the big tasty fish Tiger let out a call for Origami to come towards them. Picking up one she gave it to Tiger who happily took it swimming away. She was surprised but smiled when she saw him hand it off to his little friend before returning.

"Well, you're sweet," She squeezed his face again before giving him the other fish. "Go enjoy my lovely!"

* * *

"Who was that?"


End file.
